Organic electroluminescent device comprising two-dimensional emissive layer

1. An organic light emitting device comprising:

an anode and a cathode;

at least one organic charge transport layer positioned between the anode and the cathode;

an organic host layer positioned between the anode and the cathode; and

at least one two-dimensional emissive layer positioned at a distance of less than 10 nm from a position with the highest density of excitons within the organic host layer.

2. The organic light emitting device of claim 1 , wherein the two-dimensional emissive layer is selected from the group consisting of a transition metal dichalcogenide (TMD) active layer and a direct bandgap inorganic semiconductor.

3. The organic light emitting device of claim 2 , wherein the two-dimensional emissive layer comprises a material selected from Gallium Nitride, a group III-V direct bandgap semiconducting alloy or alloys, a group II-VI direct bandgap semiconducting alloy or alloys, or at least one monolayer of WS 2 .

4. The organic light emitting device of claim 1 , wherein the at least one organic charge transport layer comprises first and second organic buffer layers, and the at least one two-dimensional emissive layer is embedded between the first and second organic buffer layers.

5. The organic light emitting device of claim 4 , wherein the first organic buffer layer is a hole-transporting layer configured between the at least two-dimensional emissive layer and the anode.

6. The organic light emitting device of claim 5 , wherein the hole-transporting layer comprises 1,1-Bis[(di-4-tolylamino)phenyl]cyclohexane.

7. The organic light emitting device of claim 4 , wherein the second organic buffer layer is an electron transport layer configured between the cathode and the at least one two-dimensional emissive layer.

8. The organic light emitting device of claim 7 , wherein the electron transport layer comprises 4,6-Bis(3,5-di(pyridin-3-yl)phenyl)-2-methylpyrimidine or 4,6-Bis(3,5-di-3-pyridinylphenyl)-2-methylpyrimidine.

9. The organic light emitting device of claim 1 , wherein the organic host layer comprises 4,4′-Bis(N-carbazolyl)-1,1′-biphenyl.

10. A method of fabricating the organic light emitting device of claim 1 comprising the step of:

depositing the two-dimensional emissive layer using chemical-vapor-deposition.

11. A consumer product comprising the organic light emitting device of claim 1 , the consumer product selected from a flat panel display, a computer monitor, a medical monitor, a television, a billboard, a light for interior or exterior illumination and/or signaling, a heads-up display, a fully or partially transparent display, a flexible display, a laser printer, a telephone, a cell phone, tablet, a phablet, a personal digital assistant (PDA), a wearable device, a laptop computer, a digital camera, a camcorder, a viewfinder, a micro-display that is less than 2 inches diagonal, a 3-D display, a virtual reality or augmented reality display, a vehicle, a video wall comprising multiple displays tiled together, a theater or stadium screen, a light therapy device, and a sign.

12. An organic light emitting device comprising:

an anode and a cathode;

at least one organic charge transport layer positioned between the anode and the cathode;

an organic host layer positioned between the anode and the cathode; and

at least two two-dimensional emissive layers positioned within the organic host layer.

13. A consumer product comprising the organic light emitting device of claim 12 , the consumer product selected from a flat panel display, a computer monitor, a medical monitor, a television, a billboard, a light for interior or exterior illumination and/or signaling, a heads-up display, a fully or partially transparent display, a flexible display, a laser printer, a telephone, a cell phone, tablet, a phablet, a personal digital assistant (PDA), a wearable device, a laptop computer, a digital camera, a camcorder, a viewfinder, a micro-display that is less than 2 inches diagonal, a 3-D display, a virtual reality or augmented reality display, a vehicle, a video wall comprising multiple displays tiled together, a theater or stadium screen, a light therapy device, and a sign.

14. An organic light emitting device, comprising:

a substrate;

a first electrode disposed over the substrate;

at least one organic layer disposed over the first electrode;

a first portion of an organic host layer disposed over the at least one organic layer;

at least one two-dimensional emissive layer disposed over the first portion of the organic host layer;

a second portion of the organic host layer disposed over the at least one two-dimensional emissive layer;

at least one second organic layer disposed over the second portion of the organic host layer; and

a second electrode disposed over the at least one two-dimensional emissive layer

wherein the at least one two-dimensional emissive layer is a monolayer; and

wherein the at least one two-dimensional emissive layer is positioned at a distance of less than 20 nm from a position with the highest density of excitons within the first and second portions of the organic host layer.

15. The organic light emitting device of claim 14 , wherein the two-dimensional emissive layer is selected from a transition metal dichalcogenide (TMD) active layer or an emissive direct bandgap inorganic semiconductor.

16. The organic light emitting device of claim 15 , wherein the TMD active layer is at least one monolayer of WS 2 .

17. The organic light emitting device of claim 14 , wherein the two-dimensional emissive layer comprises a material selected from at least one monolayer of WS 2 , Gallium Nitride, a group III-V direct bandgap semiconducting alloy or alloys, or a group II-VI direct bandgap semiconducting alloy or alloys.

18. The organic light emitting device of claim 14 , wherein the first electrode is a transparent anode.

19. The organic light emitting device of claim 14 , wherein the at least one organic layer comprises a hole transport layer and the at least one second organic layer comprises an electron transport layer.

20. A consumer product comprising the organic light emitting device of claim 14 , the consumer product selected from a flat panel display, a computer monitor, a medical monitor, a television, a billboard, a light for interior or exterior illumination and/or signaling, a heads-up display, a fully or partially transparent display, a flexible display, a laser printer, a telephone, a cell phone, tablet, a phablet, a personal digital assistant (PDA), a wearable device, a laptop computer, a digital camera, a camcorder, a viewfinder, a micro-display that is less than 2 inches diagonal, a 3-D display, a virtual reality or augmented reality display, a vehicle, a video wall comprising multiple displays tiled together, a theater or stadium screen, a light therapy device, and a sign.